The ampersand ("&")
actually began in the days of handwritten manuscripts as a ligature of
the Latin word "et" (meaning "and") and the
letter "s" (which then often took a form resembling an
"f"). Writing books by hand was a
painstaking process, and so ligatures were often used to save
time and effort (not to mention valuableIn modern typography, many of these
old ligatures have largelyfallen out of use, at least partly
because they make it more difficultto divide words between lines.
Some publishers still use certain vowel ligatures (such as "æ")
for stylistic effect, since Englishwords aren't generally divided
between vowel combinations of thissort; this practice, however, is
increasingly rare. The ampersand,on the other hand, is still quite
widely used in certain contexts(such as business names and
informal writing), perhaps due to thefact that it still saves
significant space and effort, even by modern standards (whereas a
ligature such as "æ" barely saves space, and often requires
more effort to reproduce on today's keyboards than the simple letter
sequence "ae"). It's also exempt from the end-of-line
division problem, since the monosyllabic "and" is virtually
never broken at the end of a line anyway.